**High School Number Sense Lesson 81: Dividing a Decimal by a Decimal**

For questions 1-10 on high school tests, the most common concept we haven't covered yet is dividing decimals. It has appeared

**6 times**so far this year, with a median placement at

**question # 8**.

**Please Like our Facebook Page (**

**https://www.facebook.com/numberdojo/**

**) if you want to see new posts on your wall. I will reward you with a free concept index or flashcard file of your choice. Thank you!**

**Number Dojo Level: 85**

When dividing by decimals, I choose to

**eliminate them**altogether before dividing. Here's how:

- Count the decimal places in both the dividend and the divisor. Note how many decimal places are in each, and choose the higher number (of decimal places).
- Move the decimal that many places to the right in
**both**the dividend and the divisor. - Divide the (now) whole numbers.

**Example 1: 30.6 ÷ .4 = ___ decimal**

- There is one decimal place in each number. Move the decimal once to the right.
- The problem becomes
**306 ÷ 4**, which is**76.5**

**Example 2: 31.5 ÷ .09 = ___**

- There is one decimal place in the dividend, but two in the divisor. Move the decimal twice to the right.
- The problem becomes
**3150 ÷ 9**, which is**350**.

**Example 3: .1236 ÷ .06 = ___ decimal**

- There are 4 decimal places in the dividend, so move the decimal 4 times to the right in each number.
- The problem becomes
**1236 ÷ 600**, which is**2.06**

**Example 4: 3.636 ÷ .12 = ___**

- Move the decimal 3 times to the right in each number.
- The problem is now
**3636 ÷ 120**, which is**30.3**

**Example 5: 22.5 ÷ 0.03 = ___**

- Move the decimal twice to the right in each number.
- The problem is now
**2250 ÷ 3**, which is**750**.

**Here's a free worksheet to help you practice DivDeciDeci:**

divdecideci.pdf |

**Up Next for High School: Sub3F1/a-1/ab**